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Ulysses Spacecraft Rendezvous with Jupiter
Barbosa, David D.; Kivelson, Margaret G.
Leaving Jupiter, Ulysses Heads for the Sun's South Pole
Appenzeller, Tim
First Polymer in Space Identified in Comet Halley
Huebner, W. F.
The heavy-ion mass spectrum obtained in the inner coma of comet Halley with the PICCA instrument on the Giotto spacecraft has been examined. Short polymer chains of polyoxymethylene and their decay products are identified as the source for the spectrum with six mass peaks between about 45 and 120 atomic mass units. The properties of polyoxymethyle…
Evidence for Chain Molecules Enriched in Carbon, Hydrogen, and Oxygen in Comet Halley
Anderson, K. A.; Reme, H.; Korth, A. +7 more
In situ measurements of the composition and spatial distribution of heavy thermal positive ions in the coma of comet Halley were made with the heavy-ion analyzer RPA2-PICCA aboard the Giotto spacecraft. Above 50 atomic mass units an ordered series of mass peaks centered at 61, 75, 91, and 105 atomic mass units were observed. Each peak appears to b…
Halley's Confounding Fireworks
Kerr, Richard A.
The intensive worldwide campaign of observations of Halley's Comet repeatedly yielded data, particularly imagery, of sudden outbursts from the Comet. IUE data for Dec. 24, 1985 showed a brightness increase in the central coma by a factor of 2-3 over a 1-2 day period, followed shortly thereafter by spectra indicating a surge of ionized CO2 150,000 …
Remote Sensing of the Magnetic Moment of Uranus: Predictions for Voyager
Hill, T. W.; Dessler, A. J.
Power is supplied to a planet's magnetosphere from the kinetic energy of planetary spin and the energy flux of the impinging solar wind. A fraction of this power is available to drive numerous observable phenomena, such as polar auroras and planetary radio emissions. In this report our present understanding of these power transfer mechanisms is ap…
Ultraviolet Spectroscopy and the Composition of Cometary Ice
Feldman, P. D.
Our current knowledge of the composition of the cometary nucleus is largely inferred from observations of the gas and dust comae that are produced by sublimation of cometary ice when a comet is near the sun. During the past decade, far-ultraviolet spectroscopy from above the terrestrial atmosphere has shed new light on the physics and chemistry of…
Central Object of the 30 Doradus Nebula, a Supermassive Star
Savage, B. D.; Cassinelli, J. P.; Mathis, J. S.
R136 (HD 38268) is the central object of the 30 Doradus Nebula, a giant region of ionized hydrogen in the Large Magellanic Cloud. Observations of R136 at low and high spectral resolution with the International Ultraviolet Explorer reveal a peculiar hot object with a massive stellar wind. An outflow speed of 3500 kilometers per second and a tempera…
Io: Longitudinal Distribution of Sulfur Dioxide Frost
Matson, D. L.; Nelson, R. M.; Lane, A. L. +3 more
Twenty spectra of Io (0.26 to 0.33 micrometer), acquired with the International Ultraviolet Explorer spacecraft, have been studied. There is a strong ultraviolet absorption shortward of 0.33 micrometer that is consistent with earlier ground-based spectrophotometry; its strength is strongly dependent on Io's rotational phase angle at the time of ob…